It is often desirable to arrange conveyed objects to have a predetermined spacing along the travel direction of a conveyor belt. Such spacing enables downstream processing, such as merging objects from multiple conveying lanes into a single lane.
There are several known systems for controlling the spacing of conveyed objects. Some such systems use sensors and selectively-actuable stops that are controlled in response to information detected by the sensors. Unfortunately, such systems are relatively complex and can significantly limit the speed at which the objects are conveyed.
Other known systems use stops that are not sensor controlled. Although less complex than sensor-controlled systems, the stops of such systems are more likely to, at least intermittently, damage the conveyed objects. For instance, a conveyed object can be punctured or deformed when it runs into a partially-extended stop or when a stop is forced open against an object that is already present in the conveyance path.
In addition, it is further desirable to be able to eject individual objects for various reasons. For example, it is desirable to be able to eject defective objects from a stream of conveyed objects.